University of Washington Health Sciences Research Studies Seeking Volunteers
Definitions of Commonly Used Research Terms
Blinded studies
Blinded studies are done so that neither the
researchers' nor the participants' expectations about the
experimental treatment can influence the study results. Ordinarily,
in a "single-blinded" study, the participants do not know whether
they are in an experimental group or a
control group. In a "double-blinded" study,
neither the participants nor the researchers know which
participants are in which group.
Clinical trial
A clinical trial is a research study designed to test
the safety and/or effectiveness of drugs, devices, treatments, or
preventive measures in humans. Clinical trials can usually be
divided into four categories or "phases".
Participants in a control group are used as a standard
for comparison. For example, a particular study may divide
participants into two groups - an "experimental group" and a
"control group." The experimental group is given the experimental
treatment under study, while the control group may be given either
the standard treatment for the illness or a
placebo. At the end of the study, the results of the two groups
are compared.
Study participants in the experimental group receive
the drug, device, treatment, or intervention under study. In some
studies, all participants are in the experimental group. In
"controlled studies," participants will be assigned either to an
experimental group or to a control
group.
The FDA is the U.S. government agency that enforces
laws on the manufacturing, testing, and use of drugs and medical
devices. The FDA must approve a drug for marketing before it is
made commercially available to the public.
A human subject is a volunteer participant in a
research study.
Informed consent
Informed consent is the participant's agreement to be
in a study after being fully informed about what participating will
involve. Informed consent begins with a discussion between the
researchers and the prospective participants. The discussion
includes important information about the research study such as:
The purpose of the study
The procedures involved
The risks of participating in the study
The benefits of participating in the study
How long the study will last
How the participant's confidentiality will be protected
What will happen if the study causes harm to the
participants
That participation is voluntary
That participants are free to withdraw from the study at any
time.
Based on this discussion with the researcher, participants are
asked to sign a consent form that includes this same important
information in writing. Prospective study participants can take the
consent form home to discuss it with family and friends before
signing it. Once the form is signed, participants are given a copy
of the signed consent form so that they can review it at any time.
Participants should feel free to ask the researchers questions
before, during, and after the study. Informed consent is an ongoing
process.
Institutional Review Board (IRB)
An IRB is the group or committee that is given the
responsibility by an institution to review that institution's
research projects involving human subjects. The primary purpose of
the IRB review is to assure the protection of the safety, rights
and welfare of the human subjects. At
the University of Washington, the IRB is called the "Human Subjects
Review Committee."
Investigational or experimental device
An investigational or experimental device is a medical
device (such as an artificial heart valve or a screw used to hold
bones together) that has not yet received approval from the U.S. Food and Drug Administration (FDA) for
marketing.
Investigational or experimental drug
An investigational or experimental drug is a drug that
is not yet approved for marketing - it is not commercially
available.
A placebo is an inactive substance which may look like
medicine but contains no medicine - a "sugar pill" with no
treatment value. In some studies, the participants in a control group may be given a placebo.
Principal investigator
The principal investigator is the chief researcher -
the person in charge of carrying out a study.
Protocol
The protocol is the formal design or action plan of a
research study. The protocol explains what will be done, when, how,
and why. A particular study may be done by several researchers
around the nation or around the world. Each researcher follows the
same protocol so that at the end of the study information from all
of the researchers can be combined and compared.
Random assignment
Random assignment is assignment by chance, like
flipping a coin or pulling numbers out of a hat. This method is
sometimes used to determine who is in the
experimental group and who is in the control
group. For example, in a study with random assignment to one of
two groups, participants have a 50% chance of being assigned to
either group.
Sponsor
The sponsor is the company, research institution,
group, foundation, or government agency that funds a research
study.
